Arc-lamp globe.



G. NI. LITTLE.

ARC LAMP GLOBE.

APPLICATION FILED AUGJI. 1 913.

Patented Apr. 30, 1918.

T as

GEORGE M. LITTLE, F PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 WESTINGHOUSE ELECTRIC AND MANUFACTURING CQMPANY, A CORPORATION 9F PENNSYLVANIA.

ARC-LAMP GLOBE.

1,264LAQ5.

Application filed. August 11, 1913.

of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement 111 Arc-Lamp Globes, of which the following 1s a specification.

My invention relates to are lamps, and it has particular reference to are inclosing globes for such lamps.

In a luminous and flaming arc lamp, it is desirable that the free flow of fresh air into the arc chamber be restricted as much as possible during the operation of the lamp, because of the rapid consumption of the electrodes when burning in the presence of air which contains much oxygen. This necessitates' either a transparent or a translucent globe, the upper edge of which is adapted closely to engage a globe seat and the walls of which are usually unprovided with openings.

In service, are lamps are usually located in exposed places where they are subjected to all weather conditions, such as rain, snow, etc. Since it is substantially impossible to construct a lamp so as to shed all moisture under the severest weather conditions, water may accumulate in the lower portion of the arc-inelosing globe where it remains until it evaporates, or until it cracks the inclosing globe because of non-uniform heating of the globe during the operation of the lamp.

One object of my invention is to provide an inclosing globe which will restrict the admission of fresh air into the arc chamber and, at the same time, will drain off all the water or condensed vapor that accumulates within it.

Without attempting to illustrate the various forms that my device may assume, I will describe a specific embodiment of the principle of my invention as applied to a common form of an arc-inclosing globe, but those skilled in the art will readily understand that my invention is not limited to the specific structural details, materials, etc., disclosed herein.

The single figure of the accompanying drawing is a side view, partially in section, of an arc lamp globe that is constructed in accordance with my invention.

Referring to the drawing, an inclosing wall 1 of a transparent glass globe 2 of the Specification of Letters Patent.

Patented Apr, 3t), IQId.

Serial No. 784,032.

standard type of construction, is provided I with an opening 3 .which afl'ords communication with" the lower portion of the arc chamber a. The disk 5, made of any material such as porous earthen ware, plaster of Paris, porous cement, or the like, which permits water to percolate therethrough and which opposes the free and unrestricted passage of air therethrough, is inserted in the opening 3, substantially as shown in the drawing. In order to retain the disk in its initial position, I provide it with an outwardly flared portion 6 which engages the inner surface of the globe 2 and a portion that extends below the edge of the opening 3, thus forming an annular space which is filled with cement 7.

Any water that may accumulate within the arc-inclosing chamber because of a severe rain, will flow down on the inner surface of the inclosing wall 1 to the lower portion of the are chamber 4:. The porous earthenware- .disk 5 allows the water to percolate therethrough comparatively freely, thus draining the arc chamber of all the accumulations of water and condensed vapors. At the same time, the disk 5 substantially precludes the unrestricted ingress of fresh air into the are chamber 3, thus minimizing the rate of consumption to the electrodes. I

It will, of course, be understood that the device herein shown and described is only illustrative of means for accomplishing a specific purpose, and that details and materials of construction, and the arrangement and location of parts, may be materially varied from what is herein set forth, without departing from the spirit and scope of my invention.

I claim as my invention:

1. An arc-lamp globe adapted to provide a substantially closed arc chamber and having an opening at its lower end, and a disk that is pervious to liquids but restricts the free passage of air therethrough and is positioned in said-opening.

2. An arc-lamp globe adapted to provide a substantially closed arc chamber and having an opening at its lower end, and an inverted frusto-conical member that is pervious to liquids but restricts the free passage of air therethrough and is positioned in said, opening.

3. An arc-lamp globe adapted to provide ing an opening at its lower end, and an inverted frusto-conioal member that is pervioils to liquids but restricts the free passage of air therethrough and has an annular groove to receive the globe edge that defines said opening for securely holding it in position.

4. An arc-lamp globe adapted to provide a substantially closed arc chamber and having an opening at its lower end, and a disk that is pervious to liquids but restricts In testimony whereof, I have hereunto 15 subscribed my name this 30th day of July, 1913.

GEORGE M. LITTLE.

Witnesses B. B. HINEs, M. C. MERZ.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

